The redox activity of copper makes it an essential cofactor in numerous enzymes critical for life, but also renders it potentially toxic by promoting the formation of reactive oxygen species (ROS) that lead to cellular oxidative stress.1,2 Understanding the trafficking pathways by which cells and organisms acquire, maintain, and utilize copper while suppressing its toxicity has important ramifications for health and disease.3,4 Copper's prooxidant property is also medicinally promising if it could be harnessed to induce oxidative stress as a cancer chemotherapy strategy.5-7 New reagents that could deliver copper intracellularly in a site and time specific manner would therefore be useful both for targeted delivery of ROS-active agents and for delineating copper trafficking and utilization pathways.